I have been a T-Mobile customer since they bought VoiceStream, over a decade ago. Recently I had to port my number because the signal was weak at the location of my new job and I missed calls all the time. I was under the impression that because the latest Terms and Conditions that I renewed was in 2006 that T-Mobile would prorate my final bill; however, I was wrong. Apparently, even if you are under a very old Terms and Conditions contract, you still have to pay the whole month because the terms and conditions are subject to change.
You would think that T-Mobile would treat old customers that always paid their bill on time with more compassion.